Dozens of mountain lions live in the Santa Monica Mountains surrounding Los Angeles, but they’ve been essentially isolated in small populations by a freeway that threatens their future survival. Now state officials are back pushing for the construction of wildlife crossing that will help ensure their future survival.

For over a decade, National Park Service biologists have been tracking some of these mountain lions with GPS collars to learn more about their behavior and how they’re responding to human development. What they’ve found is that roadways and urban sprawl have made it nearly impossible for these big cats to leave the area, or for new cats to come in.

Without the ability to expand and establish new territories, they face not only the threat of deadly encounters with older members of the species but also of being forced to inbreed. Biologists worry about the impact and health consequences a lack…